The preferred embodiments relate to various systems where debris or contaminants are to be removed from lens-related apparatus in the system, and more particularly to an ultrasound architecture and method in such a system.
A lens structure as used in this document is intended to include a lens, lens cover, or other surface through which a signal (e.g., light) may pass, and where the apparatus is exposed to potential contaminants that may reduce the likelihood of successful signal passage through the apparatus. As one prominent example, in the automotive industry, cameras are assuming an important role in both Driver-Assisted Systems (DAS) and automatic safety systems. This technology commonly first appeared in relatively expensive vehicles and has migrated to less expensive ones. Indeed, the National Highway Traffic Safety Administration (NHTSA) has mandated that all new cars must be outfitted with rear view cameras by 2018. Cameras are also now being incorporated into side view mirrors to assist drivers with lane changes and currently under consideration by at least one automobile manufacturer is the possible replacement of vehicle side view mirrors with side view cameras. Besides alleviating blind spots for the driver, front cameras integrated into the windshield provide Forward Collision Warning (FCW), Following Distance Indication (FDI), and Lane Departure Warnings (LDW).
In the above context and others, and as the trend toward additional lens structure increases or becomes more ubiquitous, keeping the lens structure (e.g., lenses and lens covers) free of contaminants becomes a more prevalent need and is particularly important in safety-related applications. As one prior art approach to this issue, several manufacturers have considered a miniature spray and wiper system. This design, however, requires (1) a small pump and nozzle; (2) a motorized wiper assembly; and (3) running a hose from a fluid tank to the location of the nozzle, which may necessitate a run from the vehicle front where a fluid tank is typically located, to the vehicle back, at least for the rear view camera, which is typically located at the rear of the vehicle. As a result, this design is mechanically complex and potentially expensive.
Given the preceding, the present inventors seek to improve upon the prior art, as further detailed below.